Sri Rama Rajyotsavam is the day of Sri Rama Pattabhishekam during when Lord Sri Ram was crowned. According to Ramayana, Lord Sri Ram was crowned on Chaitra Shukla Panchami, the fifth day in bright half of Chaitra month.
In 2018, Sri Rama Rajyotsavam or Sri Rama Pattabhisheka dinotsavam date is March 27. It is observed as one of the rituals in Sri Rama Navami utsav.
Lord Sri Ram and Goddess Sita are worshipped during Sri Rama Pattabhisheka utsavam. Sri Rama Navami festival is celebrated just 4 days after this Utsav.